Extract Butea superba (Red Kwao Krua) is an extract from the Asian forests (Thailand) used in folk medicine for centuries as a means of supporting sexual activity, comparable in function with Viagra. Increasing the production of nitric oxide improves blood circulation and reduces stress and relaxes the nervous system. Active ingredients are flavonoids, glycosides, sterols (including stigmasterol). The extract is a part of dietary supplements to improve sexual performance.